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Reference — What does this symbol mean in PHP?
This is a collection of questions that come up every now and then about syntax in PHP. This is also a Community Wiki, so everyone is invited to participate in maintaining this list.
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Understanding typedefs for function pointers in C
I have always been a bit stumped when I read other peoples' code which had typedefs for pointers to functions with arguments. I recall that it took me a while to get around to such a definition while trying to understand a numerical algorithm written in C a while ago. So, could you share your tips a...
How to change the type of a field?
I am trying to change the type of a field from within the mongo shell.
14 Answers
14
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Should the folders in a solution match the namespace?
Should the folders in a solution match the namespace?
7 Answers
7
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How to calculate the number of occurrence of a given character in each row of a column of strings?
I have a data.frame in which certain variables contain a text string. I wish to count the number of occurrences of a given character in each individual string.
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Real world use cases of bitwise operators [closed]
What are some real world use cases of the following bitwise operators?
41 Answers
41
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Check if a given key already exists in a dictionary
I wanted to test if a key exists in a dictionary before updating the value for the key.
I wrote the following code:
16 Answ...
What are “named tuples” in Python?
Reading the changes in Python 3.1 , I found something... unexpected:
11 Answers
11
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pandas: filter rows of DataFrame with operator chaining
Most operations in pandas can be accomplished with operator chaining ( groupby , aggregate , apply , etc), but the only way I've found to filter rows is via normal bracket indexing
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Iterate over object attributes in python
I have a python object with several attributes and methods. I want to iterate over object attributes.
8 Answers
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